The present invention relates to a microwave cooking process which produces results similar to frying, and in particular to such a process for producing food with a crisp exterior (which is optionally browned) and a soft, tender interior.
It is well recognized that, in spite of its numerous advantages in terms of speed of cooking, the microwave cooking process cannot simulate the frying process. More particularly, the microwave process does not produce food with a crisp exterior and a soft, tender interior unless extraordinary measures are utilized, such as employing a microwave oven which includes both microwave cooking and sensible heat cooking, or the use of susceptors such as cooking containers including a metallized film or a laminated paper. "Crispiness" is defined as resistance to bite and friability (crumbliness) of the food exterior.
Conventional microwave cooking of foodstuffs having a coating--e.g., battered and breaded foodstuffs--usually results in a soggy texture at the outer surface of the food due to moisture migration from inside the foodstuff during the microwave cooking. The migrating moisture mixes with the oil of the coating at the outer food surface, the effect being to slow the heating rate down and prevent the surface temperature from exceeding 100.degree. C. (the boiling point of water) as long as there is a high level of moisture migration from the food interior to the food exterior. When all or most of the moisture has migrated from the food interior and been evaporated from the food exterior, the outer food surface temperature can exceed 100.degree. C.; however, by this time the foodstuff has a relatively dry and typically unappetizing interior.
One of the advantages of the frying process is the production of a naturally browned exterior, the browning process being a result of the reaction between a reducing sugar and an amino compound at a temperature of at least about 135.degree. C. Clearly such Maillard browning cannot occur during normal microwave cooking so long as the foodstuff has a high moisture content since the outwardly migrating moisture will prevent the surface temperature from exceeding 100.degree. C. In order to obtain the browning effect, food coatings have been used which include pre-caramelized sugar or coloring ingredients, such as paprika. These coatings have not proven to be entirely satisfactory and are generally easily detectable.
In order to make possible true Maillard browning during microwave cooking, microwave susceptors of various types have been employed, including metallized films or paper laminates. While such susceptors may increase the temperature at the food exterior sufficiently to permit the Maillard reaction to proceed, the metal and/or glue utilized in these susceptors may contaminate the foodstuff either during or after microwave cooking and thus such susceptors are not entirely satisfactory.
Accordingly, it is an object of the present invention to provide a microwave cooking process which simulates frying to produce food having a crisp exterior and a soft, tender interior.
Another object is to provide such a process which in a preferred embodiment browns the food exterior through a true Maillard reaction.
A further object is to provide such a process which is safe and economical.